Method and apparatus for emulsifying asphalt



Feb. 24, 1931. I R. K. PAINTER 1,793,957

METHOD AND APPARATUS FOR EMULSIFYING ASPHALT Filed Feb. 1, 19 0 a A 3oINVENTOR.

A05[/?7 ff. B4l/V7Z' BY l 55 ATTORNEY.

Patented Feb. 24, test ROBERT K. PAINTER, DE LOS ANGELES, CALIFORNIA,ASSIGNOR TO BITUTEGT, INCOR- PORATED, OF LOS ANGELES, CALIFORNIA, ACORPORATION OF CALIFORNIA Application filed February 1, 1930. Serial No.425,341.

This invention relates to a method and to an apparatus for emulsifyingasphalt.

The general object of the invention is to provide an improved method andapparatus 5 for emulsifying bituminous substances.

One of the specific objects of the invention is to provide a novelmethod of producing asphalt emulsions.

A specific object of the invention is to provide an improved method foremulsifying asphalt wherein the asphalt is first placed in solution.

An additional object of the invention is to A further object of theinvention is to provide a method of emulsifying asphalt or vegetablepitches wherein the asphalt or pitch is first dissolved in a solventafter which a colloidal solution is added thereto, and wherein theasphalt is thereafter precipitated in the presence of the colloidalsolution by reaction with a suitable re-agent after correcting thealkalinity of both by an addition of an aqueous solution of an organicacid to a degree whereby I will secure a superior stabilization, andwhereby I may use smaller percentages of mineral protective colloid thanhas been heretofore consistent with permanency of suspension.

A further object of the invention is to provide an improved apparatuswhich is particularly adapted for emulsifying asphalt.

Other objects of the invention will be apparent from the followingdescription taken in connection with the accompanying drawings wherein:

Fig. 1 is a side elevation partly in section showing an apparatusembodying the features of my invention and Fig. 2 is an enlarged viewshowing an emulsifier which may be used in connection with my invention.I

Referring to the drawing by reference characters, I have shown anasphalt storage provide a method of emulsifying asphalt tank at 10. Thistank is supported on suitable standards 11'. The tank 10 is connected bya pipe 12 with a measuring tank 14. This measuring tank is in turnconnected by a pipe 15 with an emulsifier 16. Suitable valves 17 and 18are provided so that the measuring tank 14 may be utilized.

A mixing tank is shown at 19. In this mixing tank I place ingredients tomake an aqueous solution of colloidal clay. This tank 19 is connected bya pipe 20 with a measuring tank 21. A pump 22 serves to force thecolloidal solution through the pipe 20. This pump 22 may be driven bybelts 23, 23' and 23" from a motor 24 or it may be driven in any otherdesired manner. The tank 21 is connected by means of a pipe 25 with theemulsifier 16. Valves 26 and 27 are arranged so that the measuring tank21 may be operated.

The delivery pipe 28 from the emulsifier is controlled by a valve 29 anddelivers into aproduct storage tank 30. The material in the productstorage tank 30 may be removed through the pipe 31 which is connected toa pump 32 and this pump delivers to a discharge pipe 33..

The emulsifier per se forms no part of my present invention but may bemade of any type. f In the drawing it is shown as comprising a casehaving a steam jacket 34 thereabouts. Steam is supplied to the jacketthrough a pipe 35 while exhaust steam passes through a pipe 36.

This jacket serves to keep the mixture in the emulsifier at the propertemperature.

The emulsifier is shown as provided with a heater 37 which may be drivenby a shaft 38 which in turn is driven by cased gears 38 from a shaft38": The shaft 38" is driven from the belt 38a.- The emulsifier isprovided with a cover 39 which serves to prevent the escape of fumes.

I will now proceed to describe my'improved method. As one example ofthis method, I may dissolve asphalt of any desired grade or I maydissolve other bituminous substances and vegetable pitches in carbontetra chloride or other suitablesolvents. The solvent used is preferablyvolatile. To the saturated solution thus formed clay corrected as toacidity with an organic I add preferably 30% of its volume of a colacid,agitating the mixture at a desired temloidal solution such as an aqueoussolution perature, precipitating the asphalt by methyl of colloidalclay. This aqueous solution of acetone in the presence of said colloidalsolucolloidal clay is preferably of adensity of tion while the whole isagitated. one pound of cla to one gallon of water. The vessel is preerably covered to prevent substances comprising first dissolving the theescape of fumes, or to collect the fumes bitumen in a solvent adding tothe solution for condensation and re-use. thus formed a colloidalsolution, precipi- The temperature is raised to 130 degrees tating thebitumen in the presence of said Fahrenheit. This done I add methylacetone colloidal solution while the whole is a iin sufiicientquantities to effect precipitation. tated, thereafter continuing theprocess y While the precipitation is going on I run the the additionofclay solution, corrected as to clay solution into the mixer. Meltedasphalt acidity with an organic acid and melted or other melted bitumenis also simultaneasphalt introduced in thin streams and drawously addedin the ratio of 2 parts'of ing off the product. asphalt or bitumen toone part of clay solu 5. The method of emulsifying asphalt tion. Theaddition of the solution of clay comprising first dissolving the asphaltin a and melted bitumen or asphalt is continued volatile solvent, addingto the saturated soluindefinitely with a stabilizer comprising tion thusformed, an aqueous solution of colan aqueous solution of an organic acidloidal clay, agitating the'mixture at a desired such as citric, acetic,malio or oxalic acid, temperature, precipitating the asphalt by in theinstance here given as an embodimethyl acetone in the presence of saidcol-- ment of my invention of 1% by volloidal solution while'the whole.is agitated, ume of a solution of 80% acetic acid, and thereaftercontinuing the processby the adthe resultant emulsified asphalt orbitumen dition'of clay solution, corrected as to acidis drawn off. Theproportions mentioned, itywith an organic acid and melted asphalt itwill be understood, serve as an example introduced in thin'streams anddrawing off only and other proportions and other rethe product.

agents may be employed if desired. In testimony whereof, I hereuntoaflix my It is a well recognized fact that when signature. asphalt orother material is precipitated ROBERT K. PAINTER. chemically fromsolution that the particles are extremely fine. With my method the finecomminution of the bitumen gives a superior product over that obtainedby other methods.

Having thus described my invention, I claim:

1. The method of emulsifying asphalt comprisin first dissolving theasphalt in a solvent, a cling to the solution thus formed an aqueoussolution of colloidal cla of which the solid content is less than 2% ofthe emulsion produced, agitating the mixture at a desired temperature,maintaining a desired true acidity by control with additions at thispoint of aqueous solution of an organic acid, precipitating the asphaltin the presence of said colloidal solution and at the proper degree oftrue acidity while the whole is agitated.

2. The method of emulsifying asphalt comprising dissolving the asphaltin a suitablesolvent, mixing the solvent with a colloidal solution andprecipitating the asphalt addition of melted asphalt in the presence ofthe colloidal solution at the proper true acidity, thereafter continuingthe process by the addition of clay solution corrected with an organicacid and the and drawing-off the product. 3. The method of emulsifyingasphalt. -comprising first dissolving the asphalt in a solvent, addingto the saturated solution thus formed an aqueous solution of colloidal4. The method of emulsifying bituminous

